A few years ago any discussion of which was better - water or air - would inevitably end in the conclusion that water was better than even the best air coolers. In fact, many would have considered it heresy to even raise the question. We are told from many directions today that water cooling is superior, and yet there are few direct comparisons of the performance of water and current air cooling.

There have been many advances in air cooling in the last few years - so much so that the best current air coolers bear almost no resemblance to yesterday's air coolers. The top air cooler of yesterday was a configuration with a small, whining, top-mounted fan with a heavy copper heatsink and no heatpipes. This is a far cry from today's best air coolers. Now the most successful of current air cooler designs feature heatpipe towers with quiet side-mounted 120mm fans blowing toward a rear exhaust.

The multiple liquid-filled heatpipes and the large, quiet, high-output fans in use today have taken air cooling to new performance levels. Our testing here at AnandTech supports the vastly superior performance of the heatpipe tower compared to the older air cooling designs. With these results in mind, it is time to revisit the question: is water cooling still the best performer?

Certainly the reasonably priced self-contained water coolers have provided mixed test results compared to the top air coolers. The small Xigmatek AIO provided good results for its size, but the larger Evercool Silver Knight was somewhat disappointing in performance. It was reasonably clear in test results though, that the self-contained units could compete in the notch below the top of the tested air coolers, but not the top air coolers of today. None of the self-contained water coolers really cooled better or could reach the same high overclocks we saw with the best air designs. This raised the question of how "real" water cooling systems would compare.

Water cooler designs have not been completely static while air cooler design has been evolving. Water cooling manufacturers have been working toward simpler designs that are less intimidating for the average computer enthusiast. This involves several different approaches. Some look to move all of the water cooling components inside the case while others are looking at new ways to move water cooling outside the case; we will be looking at both approaches today, the former with the Swiftech H2O120 Compact and the latter with the Corsair Nautilus 500. Whichever approach they have taken, the water cooler manufacturers claim combining complete top-line pumps, waterblocks, reservoirs and radiators has resulted in top-line water cooling results with a much easier installation than traditional water cooling.

The Swiftech H2O-120 Compact combines water cooling components inside the case. Swiftech reduces the traditional four components of a water cooling system to two components. The water block and water pump are combined into the Apogee Drive Block and the radiator and reservoir are combined. By merging components the H2O Compact requires just one set of connecting hoses in the water cooling system.

According to Swiftech this simplified water system still uses the top individual components in the combined components so performance is not compromised. The simpler H2O-120 Compact also claims much easier installation, with just 15 to 20 minutes required for a complete internal installation. All of this water cooling performance also comes at a cheaper price than is typically seen with a water cooling kit. The H2O Compact was just introduced and is selling for around $150, but Swiftech tells us they expect the street price for the H2O-120 Compact kit to settle in at around $129.

The Corsair Nautilus 500 uses a different approach to easier installation. Components remain similar to the more traditional water cooling parts, but everything except the CPU water block is integrated into an external cooling appliance. This also reduces water connections to two tubes for a much simpler and faster installation. Corsair claims the Nautilus 500 can be installed in 8 minutes, which is certainly as fast as most air cooling installs.

The Corsair Nautilus 500 also comes at a cheaper price than many other water cooling kits. Where most kits are in the $200 or higher price range, the Corsair sells for about $150 or even less. This places the Nautilus 500 in the same basic price group as the H2O-120 Compact.

Both Corsair and Swiftech claim they have not compromised in quality or performance with the simpler-to-install systems. Both say they combine top-line pumps, water blocks, reservoirs and radiators to insure top-line water cooling results with a much easier installation than traditional water cooling. In fact it appears both Corsair and Swiftech use similar components in their systems that are arranged in different configurations.

The big question then is performance. Do the Swiftech H2O-120 Compact and Corsair Nautilus 500 actually outperform the top air coolers? Are they quieter than today's best air coolers as advocates of water cooling claim? These are not frivolous questions since either water system costs two to three times the price of the top air coolers. Finally, are there other advantages to these water systems that make them a better choice even if performance is less than standout? Do the Compact H2O and/or the Nautilus 500 claim the title of best cooling system tested at AnandTech?

I wonder what was wrong with your setups and your pumps. Having had the Corsair Nautilus 500 unit, and the pump the Swiftech kit is based upon, something is/was seriously wrong with your setup or pumps.

The Corsair unit's fan, at least in the one I used, drowned out the pump completely.

The Laing pump in the Swiftech kit, the same pump in the Corsair kit by the way, is sitting in my computer and is utterly silent....completely drowned out by any of the four fans in the case....three Scythe S-Flex "E" fans, at 22 dBA on full speed, and an Antec SpotCooler on lowest speed (the Antec is the loudest fan in the case, btw.)

I'd almost hazard a guess that both kits, after being set up, still had a bubble/pocket of air in the pump. The Laing pump can get quite noisy if no completely bled of air.

Otherwise, there was a mechanical fault in both your kits' pumps as the Laing is almost completely silent when working as attested to by the hundreds of people using those pumps and hearing absolutely nothing from them when being used.

That's not hwo I meant it, of course you shouldn't mod the kits for testing. I was just saying that the Laing is not a bad pump for custom setups, in fact, it's pretty much the best pump for most setups if you use a mod top, which makes a big difference. I don't think I've ever seen a pic om someone using it without a mod top, but dozens with all kinds of mod tops. Reply

I first thought there was a pump defect as well. So I acquired FIVE Apogee drive blocks from different sources and all measured similar dbA noise levels. There was also the 6th pump in the Corsair Nautilus 500.

Subjectively the pumps were relatively quiet because the noise frequencies appear to fall in a freqency range that is not particularly annoying. However, our standard sound meter said measured noise was pretty high. We stated this in the review and also commented the pump noise was not annoying to our ears, but it may be to others. Measure the noise of your system and let us know what you find. Reply

We did not state water cooling was always inferior to the top air coolers. We said, based on these test results and others we have run recently, that you would need to spend more than $300 on a water cooling system that might outperform the best air coolers.

At more than 4 to 6 times the price of a top air cooler most readers would not conseder that good value.

I actually agree with your comments, but please tell us the total cost of the water cooling setup you say is needed to beat the best air coolers. Reply